What is the general form of the equation of a circle with its center at (-2, 1) and passing through (-4, 1)? Precalculus Geometry of an Ellipse General Form of the Equation 1 Answer ali ergin Mar 22, 2016 #(x+2)^2+(y-1)^2=4# Explanation: #"first ; let's find the radius of circle:"# #"Center: "(-2,1)# #"Point: "(-4,1)# #Delta x"=Point(x)-Center(x)"# #Delta x=-4+2=-2# #Delta y"=Point(y)-Center(y)"# #Delta y=1-1=0# #r=sqrt(Delta x^2+Delta y^2)# #r=sqrt((-2)^2+0)# #r=2" radius"# #"now ; we can write the equation"# #C(a,b)" center's coordinates"# #(x-a)^2+(y-b)^2=r^2# #(x+2)^2+(y-1)^2=2^2# #(x+2)^2+(y-1)^2=4# Answer link Related questions How can I tell whether an ellipse is a circle from its general equation? What conic section has the equation #x^2+y^2+12x+8y=48#? What comic does the equation #4x^2+4y^2=16# represent? How do I find the radius of a circle from its general equation? How can a general equation tell me whether a conic section is a circle or an ellipse? What conic section does the equation #x^2 + 4y^2 - 4x + 8y - 60 = 0 # represent? What conic section does the equation #−x+2y+x^2+xy+y^2=0# represent? What conic section does the equation #2x^2+4xy+6y^2+6x+2y=6# represent? What is the equation of a circle with a radius of 5? How do you find equation of ellipse with two vertices V1(7,12) and V2(7, -8), and passing... See all questions in General Form of the Equation Impact of this question 6091 views around the world You can reuse this answer Creative Commons License